1.1: n-butyllithium / tetrahydrofuran / 0.75 h / -78 °C / |Inert atmosphere 1.2: 1 h / -78 °C / |Inert atmosphere 2.1: sodium tetrahydroborate / ethanol / 0.5 h / 0 °C 3.1: hydrogenchloride / tetrahydrofuran / 20 °C 4.1: sodium tetrahydroborate / ethanol / 0.5 h View Scheme

1: 6-bromo-2,2-dimethyl-4H-1,3-benzodioxin With n-butyllithium in tetrahydrofuran; hexane T=-78°C; 2 h; 2: N,N-dimethyl-formamide in tetrahydrofuran; hexane T=-78 - 20°C; Further stages.;

1.1: n-BuLi / tetrahydrofuran; hexane / 2 h / -78 °C 1.2: 94 percent / tetrahydrofuran; hexane / -78 - 20 °C 2.1: 81 percent / HCl / acetonitrile; H2O / Heating View Scheme